Process and apparatus for treating oils



Dec. 29,- 1931; R. T. POLLOCK 1,339,049

PROCESS AND APPARATUS FOR TREATING OILS Original Filed May 9, 1921 Ira/@1202: iflm 7fobew T Bung JMOKM Q Patented use. 29, 1931 UNITED STATES PATENT? OFFICE ROBERT T. POLLOOK, OF NEW YORK, N. Y., ASSIGNOR TO UNIVERSAL OIL PRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA rnocnss m nrrnnn'rus ron TREATING OILS Application filed May 9, 1921, Serial 1E0, 467,908. Renewed March 15, 1928.

products.

Among the salient objects of the invention are to provide a process in which the oil is heated to a cracking temperature and vaporized in alternate enlarged expansion chambers where the carbon which is deposited during vaporization is permitted to accumulate and collect; to provide a process in which, after the accumulation of the carbon, air is introduced to the carbon body and it is consumed as a combustible fuel, thecombustion gases being used in continuing the oper ation of the process; to provide a process in which alternate expansion chambers are used, first as expansion or vaporizing zones and then as combustion chambers where the col- .lected carbon is consumed as fuel in heating oil to be cracked; to provide a process in which the uncondensable gases are collected and returned and used as additional fuel in the combustion chambers; toprovide a process which is economical and eflicient and one which may be operated continuously over considerable lengths of time, the carbon difficulties being obviated by the consumption of the carbon body as a fuel in heating the oil; to provide an apparatus for carrying out the described process and'in general to provide an improved process and apparatus of the character referred to.

The single figure in the drawing is a diagrammatic side elevational view of the apparatus. v

The raw oil is introduced from any convenient source through the inlet pipe 1 and may be directed through the pipe 2 controlled by a valve 3 to the top of the dephlegmator 4 where it i's-coursed down in the direction opposed to the vapors rising in the dephlegmator or it may be conducted directly=to the pipe 5 controlled by a valve 6 to the reflux line 7 controlled by a valve 8 by means of which the reflux condensate is drawn from the dephlegmator. Whichever may be the ,method of introducing the raw oil, it pzsses through the line 7 to the heating tu s9 mounted in a furnace 10. Here it is heated to a cracking temperature and is passed through the transfer line 11 to a horizontally positioned line 12 in which are interposed valves 13 and 14 controlling the flow of heated oil to the combustion chambers 15 and 16 respectively. For the purpose of this explanation it is assumed that the chamber 15 is being used as a combustion chamber and the chamber 16 is being used as an expansion chamber. In this connection, it must, however, be understood that these chambers may be alternately used as expansion chambers and combustion chambers, the heated oil be-' ing introduced to each when used as an expansion chamberthrough the upturned portions 17 of thehorizontal transferline 12.

-When using the chamber 15 as a combustion chamber in the initial stages of the process, the oil burner 18 is used to supply heat to the chamber. This enlarged chamber comprises the vertical vapor riser 22 is kept closed when the chamber is being used as a combustion chamber. In the top of both of the chambers 15 and 16 are the vertical portions of the ducts 19 which unite to form the duct 20 leading to the furnace 10. Sleeves 23 which may be raised when the pressure-tight covers 24 are bolted in place may be lowered when the chamber is used as a combustion chamber to seal the duct and direct the combustion gases to'the heating tubes without susceptible loss due to short circuiting of the gases or from leakage, in the connections. The combustion gases from the chamber 15 pass over the heating tubes and out through the stack 25. The oil passing through the heating tubes is directed through the transfer line to the vapor chamber 16, the valve 14 being 0 ened and the valve 13 being closed. Here t e oil is vaporized, the vapors passing off through the riser 26 controlled by a valve .27 through the vapor line'28 regulated by a valve 29 and thence to the dephlegmator 4 where they may be subjected to the dephlegmating action of the raw oil in case it is being introduced to the top of the dephlegrnator or they may be merely subjected to the dephlegmating action of the atmosphere as desired. In any case, the uncondensed. portions rise through the dephlegmating column and pass off through the line 30 to the water condenser 31, the distillate being collected in the receiver 32 which is equipped with a liquid drawofi' line 33 controlled by a valve 34. The uncon-- densable gases may be drawn off from the receiver through the line 35 regulated by a valve 36 and may be collected in gas reservoir 37 from which it may be taken off through a line 38 in which is interposed a throttle valve 39 and pass to a gasometer 40 which serves as a gas reservoir and from which the gas may be returned and used as combustible fuel through the line 41 communicating with the chamber 15 and line 42 communicating with the chamber 16. To return to the evaporation of the oil in the expansion chamber 16, this evaporation or vaporization is attended by a deposition of carbon which collects and accumulates in the bottom of the chamber until it has built up a substantial carbon body and due to the fact that conditions are such that a greater part of the liquid content of the oil is removed in the vaporization, an oil sludge or porous carbon mass will be collected in the chamber. When this carbon has collected to an amount which hinders or retards the vaporization of the oil in the chamber, the heated oil fromthe heating tubes 9 is then directed to the chamber 15 by closing the valve 14 and opening the valve 13.

It is essential that simultaneous with this alternation of theoil flow, that the valve 27 in the vaporizer 26 is closed and the valve 21 in the riser 22 is opened. It is also necessary that pressure tight cap 24 be bolted down upon the open outlet in the top of the chamber 15 connected with the duct 19 so that the vapors released from the oil will not escape from the chamber except through the vapor line. A. valve 43 in the duct 19 will now be line-45 from the air compressor 46 to the carbon body which has been permitted to collect in the chamber 16; this carbon body being at a high temperature is immediately ignited and as the pressure-tight cap 24 has been removed from the top of the chamber 16 and the sleeve 23 lowered in place, the gases of combustion will pass'out through the duct 19 to the furnace 10 and thence to the stack as did the gases from the chamber 15. The air passing through the pipe 45 is under manual control by reason of the valve in the feed lineso that the quantity of air admitted to either chamber may be so re lated as to cause the proper combustion o the ignited carbonaceous fuel as will produce gases of a sufiicient temperature to properly crack the oil passing through the coils around which said heating gases pass. Furthermore, the control of the temperature of the heating gases generated in the combustion chambers 15 and 16 may be largely regulated by the operation of the manually operable valves 48 and 44 which control the draft in said chambers by reason of their establishing communications between said chambers and the gas stack. A gas burner 47 is positioned in the furnace 10 in order to supply additional heat in case the heat from the combustion chamber is not sufficient. With the introduction of air, the carbon in the chamber 16 is gradually consumed, and the heat generated and utilized in heating the raw oil. During this cycle of operation, the oil which is introduced to the vapor chamber 15 is being evaporated therein and the carbon is permitted to accumulate in the chamber 15 while the vapors pass off through the riser 22 and proceed through the system by identically the same route as the vapors released from the oil in the chamber 16 as previously'explained. If the collection of carbon which is being-consumed in the chamber 16 is insuflicient to supply heat enough for the oil to be treated and producing a similar carbon body in the chamber 15, a gas burner in the chamber 16 mounted on the line 42 may be ignited or an oil burner on the oil line 48 may be used to furnish additional heat to the heating tubes. Residuum drawofis 49 are supplied to the respective chambers.

In this manner, the chambers 15. and 16 may be alternately used as expansion and combustion chambers due to the fact that they are lined with non-fusible cement or brick and high temperature may be maintained in the chamber and high pressures imposed in order to affect the proper cracking of the oil or combustion when used as a combustion chamber. It is essential, of course, that the caps 24 be pressure tight in order to prevent leakage of the vapors when either of the chambers are employed as expansion chambers and it will be understood that two or more chambers may be used in the system in this manner.

' By utilizing the carbon and uncondensable gas in this manner, it is possible to treat the oil both economically and efficiently and practically obviate the carbon difiiculties common to hydrocarbon distillation systems. In addiplace in the presence of a large body of heated oil is of advantage in that the vaporous fractions are of a more uniform end point and the distillate is of a more uniform quality having less of the wild fractions so common to cracked distillates. It may be desirable also to insert one or more banks of heating tubes between the enlarged chambers and the single unit as shown in the drawing may be multiplied to form a battery of units where large quantities of oil are to be treated. Such an apparatus as shown may be used for treating Texas, California and Mexican oils due to the fact that excessive carbon content of the oil is particularly adapted to this type of construction, as a greater quantity of the carbon is supplied for subsequent combustion. The process, when continuously operated, is adaptable for treating large quantities of oil and particularly the heavier oils whose excessive carbon content has made the oils objectionable due to the fact that carbon diiiiculties in the vaporizing and heating zone have necessitated frequent shutdowns for cleaning.

I claim as my invention:

1 A process for treating oils, consisting in passing the oil through a heating zone and raising it to a cracking temperature therein, supplying heat thereto from alternate chambers independent of said heating zone used successively as vaporizing and combustion chambers, permitting the heated oil to vaporize in one chamber and the precipitated carbon to collect therein, While using an alternate chamber as a combustion chamber and then changing the oil flow to the combustion chamber when the carbon has accumulated to the desired degree in the chamber being used as a vaporizing chamber while using the initial vaporizing chamber as a combustion chamber. v

2. A process of cracking hydrocarbon oils, consisting in passing oil through a heating zone where it is raised to a cracking temperature, in permitting the heated oil to vaporize in a large insulated chamber located outside of saidheating zone and in which chamber carbon precipitates, in supplying the heat for cracking said oil from the combustion of precipitated carbon that has collected in an alternate vaporizing chamber by consuming said carbon and passing the heating gases into said oil heating zone.

3. A process of cracking hydrocarbon oils, consisting in passing oil through a heating zone where it is raised to a cracking temperature while under a superatmospheric ber.

ROBERT T. POLLOCK.

pressure, in generating heat from carbon collected in alternate chambers used successively as vaporizing and combustion chambers .in communication with said heating ,zone, in permitting the heated oil to vaporize in one of said chambers and carbon to precipitate therein while consuming carbon that has precipitated in an alternate chamber to heat the 

